dont run doParallel in tests

Author: mnwright

R/impute.R

@@ -26,14 +26,20 @@
 #'   iris_na[sample(1:nrow(iris), 5), j] <- NA
 #' }
 #' 
-#' # Parallelization with doParallel
-#' doParallel::registerDoParallel(cores = 2)
-#' 
 #' # Single imputation
 #' iris_imputed <- arf::impute(iris_na, m = 1)
 #' 
 #' # Multiple imputation
 #' iris_imputed <- arf::impute(iris_na, m = 20)
+#' 
+#' \dontrun{
+#' # Parallelization with doParallel
+#' doParallel::registerDoParallel(cores = 4)
+#'
+#' # ... or with doFuture
+#' doFuture::registerDoFuture()
+#' future::plan("multisession", workers = 4)
+#' }
 impute <- function(x, 
                    m = 1, 
                    expectation = ifelse(m==1, TRUE, FALSE),